Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/tools/testing/nvdimm/dimm_devs.c b/tools/testing/nvdimm/dimm_devs.c
new file mode 100644
index 0000000..57bd27d
--- /dev/null
+++ b/tools/testing/nvdimm/dimm_devs.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright Intel Corp. 2018 */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/nd.h>
+#include "pmem.h"
+#include "pfn.h"
+#include "nd.h"
+#include "nd-core.h"
+
+ssize_t security_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct nvdimm *nvdimm = to_nvdimm(dev);
+
+	/*
+	 * For the test version we need to poll the "hardware" in order
+	 * to get the updated status for unlock testing.
+	 */
+	nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
+
+	if (test_bit(NVDIMM_SECURITY_DISABLED, &nvdimm->sec.flags))
+		return sprintf(buf, "disabled\n");
+	if (test_bit(NVDIMM_SECURITY_UNLOCKED, &nvdimm->sec.flags))
+		return sprintf(buf, "unlocked\n");
+	if (test_bit(NVDIMM_SECURITY_LOCKED, &nvdimm->sec.flags))
+		return sprintf(buf, "locked\n");
+	return -ENOTTY;
+}